But it begs the question, why does a girl who was obviously hot before want to do that to herself?

Pwer, I firmly believe that it is from a lack of power, and once women obtain the paper from changing themselves---no longer bound by "man's" constraints, it is addictive to them, you see this more in Western countries, although there are those extreme examples in other places...but, in most places, women who work out try to extablish a balance.